Embodiments herein generally relate to using power saving sleep modes in devices and more particularly to methods and system for optimizing the use of such power saving modes.
The reduction of energy consumption is becoming a major issue in many areas. In addition to high quality solutions, customers are expecting “greener” products. This is particularly true for Managed Print Services contracts where the goal is to minimize the energy consumption of fleets of printers, but also for other types of devices such as air conditioning systems for facilities or ticketing devices for public transportation.
In view of this, manufacturers of devices, such as printing devices, are making greater use of power-saving modes to allow their devices to consume less power. Power savings modes are reduced-power modes that use less power than ready modes; however, in power saving mode, most device functions are not available. When entering power-saving modes, most devices disconnect the power being supplied to all but a few devices needed to recover from the power saving mode.
For example, an “active mode” (sometimes referred to as an operational mode) can be defined as the mode in which the device, while connected to a power source, is producing useful work. To clarify, the low end or minimum power draw of active mode is idle. The high end of active mode would be the maximum power draw capable by the device. The “idle state” (sometimes referred to as a ready mode, idle mode, standby mode, etc.) is the state in which the operating system is operational and warmed-up, the machine is not asleep, and activity is limited to those basic functions that the device starts by default. Idle state is considered a subset of the active mode. A “sleep mode” (sometimes referred to as a reduced-power mode) is a lower power state that a device enters automatically after a period of inactivity or by manual selection. A device with sleep capability can quickly “wake” in response to inputs. Devices may have more than one sleep mode. The lowest power consumption mode which cannot be switched off (influenced) by the user and that may persist for an indefinite time when the device is connected to the main electricity supply and used in accordance with the manufacturer's instructions is an “off mode.”
Thus, power saving sleep modes only supply power to a few device elements to save power, yet allow the device to return to full operational mode (active mode) more quickly when compared to the time needed to reach full operational mode from a full off condition (where substantially all systems are disconnected from the power supply). The active power mode is one that provides the fastest operation, provides availability of all features, and consumes the most power. Different power saving modes consume different amounts of power, but all power saving modes consume less than the active mode, which consumes the most power. Such power saving sleep modes are begun when the device has not received any input from users or other devices within a specific time period (referred to commonly as a “time-out” period). Such sleep modes generally start a routine that saves certain information in the storage device, selects which items will be disconnected from the power supply, resets various flags, etc., and then disconnects the power supply from selected elements of the device that will not be powered during the sleep mode.